Machine-switching device



C. L. GOODRUM.

MACHINE SWITCHING DEVICE.

APPLICATION FILED FEB. 24, I9I9.

1,375,692. I Patented Apr. 26, 1921.

UNITED STA'I'Efi PATENT OFEEE.

CHARLES Ii. GOODRUM, NEW YORK, N. Y., ASSIGNOR TO WESTERN ELECTRICCOMPANY, INCORPORATED, 013 NEW' YORK, N. Y., A CORIPORATION OF NEW YORK.

MACHINE-SWITCHING DEVICE.

Specification of Letters Patent.

Patented Apr. 26, 1921.

Application filed February 24, 1919. Serial No. 278,927.

To all whom it may concern: 1

Be it known that I, CHARLES L. GoonnUM, a citizen of the United States,residing at New York, in the county of New York, State of New York, haveinvented certain new and useful Improvements in Machine- SwitchingDevices, of which the following is a full, clear, concise, and exactdescription.

This invention relates to automatic or semi-automatic telephoneswitching systems, and more particularly to switching systems employingselector switches of the powerdriven panel-bank type.

The object of this invention is to provide an improved form of apparatusand organization of circuits, whereby the time for setting up a callbetween a calling and a called subscriber is reduced to a minimum.

In accordance with the general features of this invention, a selectorswitch for connecting the calling subscriberwith the desired trunk lineis adapted to be operated directly in response to impulses from thecalling subscribers station, to move from one group of trunk terminalsto the next, and to be moved over the successive groups and intooperative relation with the required group of terminals in response tothe operation of the power-drive mechanism and under control of theimpulse-sending mechanism. V

In the preferred form of this invention, the step-by-step mechanism andthe powerdrive mechanismior controlling the movement of the brush shaftare made to operate upon the samemember, namely, the tape or strip towhich the brush shaft is connected, and the operation of this brushshaft in response to the step-by-step mechanism establishesconditionsfor continuing the operation of the brush shaft in response to the powerdrive mechanism until the se-' lected brushes havebeen moved across onegroup.

The drawing is a diagram of circuits and apparatus embodying thefeatures of this invention.

Referring to the operation of this system,

when the subscriber at A removes his re-' ceiver from the switch-hookfor the purpose of making a. call, the wlres leadmg from this substationwill be automatically confor a brush selecting magnet 9 which, inoperating causes a pawl 10 to engage notches 11-.11 in one edge of atape 12 to raise a rod 13 carrying brush sets 14 and 15. Upon itsopposite edge, the tape 12 is provided wlth a plurality of notches16-16, adapted to be engaged by a holding pawl 17 to re tain the brushshaft in a position to which it is moved by the brush-selecting magnet 9and also by the power-drive mechanism.

The first set of impulses from the calling subscribers dial selects theset of brushes which is to be tripped by means of a brush trip rod 18controlled by a trip magnet 19. As shown, the brush trip rod 18 isprovided with a plurality of angularly extending fingers EEO-20, whichare so spaced upon the rod 18 that each will engage a tripping arm 21 ofa particular brush set in response to a diiierent number of verticalimpulses. That is to say, the lowermost set of brushes 1 1 may be set tobe tripped in response to one impulse of the brush-selecting magnet, thenext set 15 being set to be tripped in'response to two steps of thebrush-selecting magnet, and so on. The general: arrangement or" thecontact bank, brush sets and tripping mechanism may be similar to thatdisclosed in Patent No. 1,123,696, issued January 5, 1915, to-E. B;Craft and J. N. Reynolds.-

At the end of the first series of impulses relay 7 remains energized,and a slow release relay 25 which is pulled up at the first re- 20thereon, to trip the desired set of brushes upon the next upwardmovement of the brush shaft 13. WVhen the side switch arm 28 goes intoposition 2 a circuit is completed for up-drive magnet 29 from battery,through a commutator brush 30 carried on the upper end of the brushshaft 13, over conductor 31, through up-drive magnet 29, over conductor32, through side switch arm 28 in position 2, and left-hand frontcontact of relay 8, to ground.

The switch shaft 13 now moves upwardly until the commutator brush 30passes from the first conducting segment 35 onto an insulating stripbetween the segment 35 and the next segment 36. As the brush shaft 13starts upwardly, the desired set of brushes is tripped and is, at theend of the powe driven movement of the brush shaft 13, brought intoposition directly below the first row of contacts of the bank. Thesubscriber again operates his calling dial which completes a circuit forthe brush-selecting magnet 9, which causes the commutator brush 30 tomove onto the next conducting segment 36, whereupon the up-drive magnet29 causes it to move over the first group of terminals and come to restwith the commutator brush 30 on the insulating segment between conductinsegment 36 and the succeeding one above it. This movement is very rapidand takes place before the second impulse from the calling dial isreceived through the brush selecting magnet 9. The next impulse againoperates the magnet 9 to move the brush 30 onto the next conductingsegment, thereby again completing the circuit for the up-drive magnet29, and this operation is repeated until the desired group of terminalshas been selected.

At the termination of the second series of impulses from the subscribersdial, the side switch magnet 26' which was energized upon the firstretraction of the armature of 7 again falls ofi and moves the sideswitch arms into position 3. In position 3 the brush-selecting magnet 9is again energized over a circuit from battery, through the winding ofthe magnet 9, through an armature and back contact of up-drive magnet 29and side switch arm 37 in its third position. This moves the commutatorbrush 30 onto the next conducting segment, and trunk-hunting now takesplace. During this hunting the up-drive magnet 29 is energized through acircuit which is completed from battery, through commutator brush 30,over conductor 31, over conductor 32, through side switch arm 28 inposition. 3, over conductor 38, to back contact and mature of the escapemagnet 26. This magnet 26 acts also as a test relay and is operatedthrough ground on the test contact of an idle trunk, which is appliedthereto in a manner similar to the manner in which.

it is applied to the test contact 90 of the trunk leading to theselector shown in the drawing, that is, from ground to the back contactof the line relay and back contact of the first slow relay and sideswitch wiper 48 in its first position.

When the test brushes of a selected brush set engage the contacts of anidle trunk, that is, one on which ground is present, the escape magnet26 pulls u over a circuit which is completed from battery, through thewinding of escape magnet 26, over conductor 40, through side switch arm41 in position 3, over conductor 42, and through the test brushes, toground. This energization of the escape magnet causes the side switcharm to move into position 4 and completes the talking and releasecircuits of the selector. The operation of the side switch magnet, is socontrolled that the first two steps of the side switch arms take placeupon the deenergization of the escape magnet and the last step upon theenergization.

The switch may be released by placing direct ground on the third contactof the succeedlng switch in a manner well known, which completes thecircuit from battery, through the down-drive magnet 45, which alsocontrols the release of holding pawl 17 from tape 12. This circuit willbe from battery, through the winding of clown-drive magnet 45, throughan off-normal contact 46, over conductor 47, through the side switch arm48, over conductor 49 and conductor 42, to the test brushes of the set.lVhen the down-drive magnet 45 pulls up, it closes a contact 50 whichcompletes a locking circuit for the magnet 45 which is opened when theswitch is completely restored to normal and the off-normal contact 46 isopened.

The general construction of the side switch is preferably similar tothat disclosed in Patent No. 1,252,420, issued January 8, 1918, to O. F.Forsberg. The method of restoring the side switch in the present systemmay be similar to that employed in such patent.

The closely spaced notches upon the edge of the strip 12 to be engagedby the pawl 10 of the magnet 9 are spaced apart the distance betweenadjacent sets of stationary contacts. The remaining notches on strip 12are spaced apart a distance equal to the space occupied by a group ofcontacts. The notches for the holding pawl 17 are spaced apart thedistance between adjacent contact sets throughout the length of thestrip 12.

What is claimed is:

1. In a telephone switching system, subscribers impulse-sendingmechanism, sta tionary contacts arranged in groups and subgroups, amovable carriage, contacts mounted thereon, and step-by-step mechanismand power'drive mechanism operat ing'directly upon said carriage inresponse to the operation of'said impulse-sending 2. In a telephoneswitching system, subscribers impulsesending mechanism, sta tionarycontacts arranged in groups and sub-groups, movable contacts, a carriagefor said movable contacts, step-by-step mechanism operating directly inresponse to the operation of the impulse-sending mechanism, andpower-drive mechanism operating indirectly in response to the operationof said impulse-sending mechanism but simultaneously therewith to movesaid movable contacts into engagement with a desired set of stationarycontacts in a desired group and sub-group, due to the mechanicalcooperation of said step-by-step mechanism.

3. In a telephone switching system, a plurality of sets of stationarycontacts divided into groups and sub-groups, movable contacts, acarriage for said movable contacts, step-by-step mechanism operatingdirectly upon said carriage to move its contacts between adjacentsub-groups of stationary contacts, and power-drive mechanism operatingupon said carriage to move its contacts across said sub-groups ofstationary contacts to select a desired set of stationary 'contacts in adesired group and sub-group.

4:. In a telephone switching system, subscribers impulse-sendingmechanism, a plurality of sets of stationary contacts divided intogroups, movable contacts, a carriage for said movable contacts,step-by-step mechanism adapted to operate directly upon said carriage inresponse to the operation of the impulse-sending mechanism to move themovable contacts between adjacent groups of stationary contacts, andpowerdrive mechanism operated under control of said impulse-sendingmechanism and simultaneously therewith to move the movable contactsacross the groups of stationary contacts.

5. In a telephone switching system, subscribers impulse-sendingmechanism, stationary contacts arranged in groups and sub-groups,movable contacts, a carriage for said movable contacts including anoperating member, and step-by-step and powerdriving mechanism adapted toengage and drive said operating member in response to impulses from saidimpulse-sending mechanism and to move said movable contacts intoengagement with a desired set of stationary contacts in a desired groupand sub-group, simultaneously with the operation of said impulse-sendingmechanism.

6. In a telephone switching system, subscribers impulse-sendingmechanism, stationary contacts, movable contacts, a carriage' for-saidmovablecontacts including a fiat-surfaced member having notches upon oneedge thereof, step-by-step mechanism adapted to engage-the" notched edgeof said flat-surfaced member to move said movable contacts directly; inresponse to the operationof; the impulse'sending mechanism, and powerdrive mechanism adapted to engage thefl'at: surface of saidflat-surfaced member to move said carriage simultaneously with theoperation of said impulse-sending mechanism.

7. In a telephone switching system, subscribers impulse-sendingmechanism, a plurality of sets of stationary contacts divided intogroups, movable contacts, a carriage for said movable contacts,step-by-step operated mechanism directly responsive to saidimpulse-sending mechanism for moving said movable contacts betweenadjacent groups of stationary contacts, power-drive mechanism for saidcarriage, and an operating circuit for said power-drive mechanism established in the movement of said carriage in response to thestep-by-step mechanism to move said movable contacts successively acrossthe groups of contacts at each impulse of said impulse-sendingmechanism.

8. In a telephone switching system, subscribers impulse-sendingmechanism, stationary contacts, movable contacts, a carriage for saidmovable contacts, step-bystep mechanism, power-drive mechanism forimparting motion to said brush carriage, a movable brush, a drivingcircuit for said power-drive mechanism extending through said movablebrush, and means including said step-by-step mechanism to advance saidbrush in response to the operation of said impulse-sending mechanism.

9. In a telephone switching system, subscribers impulse sendingmechanism, stationary contacts arranged in a panel contact bank, amovable carriage, contacts mounted thereon, and a step-by-stepmechanismand power drive mechanism operating directly upon said carriagein response to the operation of said impulse sending mechanism to movesaid movable contacts into engagement with a desired set of stationarycontacts.

10. In a telephone switching system, a plurality of sets of stationarycontacts divided into groups and mounted in a panel contact bank,movable contacts, a'carriage for said movable contacts, and step-by-stepmechanism operating directly upon said carriage to move said contactsbetween adjacent groups of stationary contacts, and a power drivemechanism operating upon said carriage to move its contacts across saidgroups of stationary contacts.

11. In a telephone switching system, subscribers impulse sendingmechanism, a multiple contact bank of the panel type, a

brush carriage, a plurality of normal inoperative brush sets mountedthereon, a step-by-step mechanism and power drive mechanism operatingdirectly upon said brush carriage in response to the operation of saidimpulse sending mechanism, means to render operative a desired one ofsaid brush sets under the control of said stepby-step mechanism,rmeansto select a group of contacts under the joint control of said 10 my namethis 18th day of February A. 1)., 15

CHARLES L. GOODRUM.

